Saddle for use with flexible wraparound printing plates



N. .1. POZNIAK 3,416,447

SADDLE FOR USE WITH FLEXIBLE WRAP-AROUND PRINTING PLATES Dec. 17,1968

Filed Oct. 10, 1966 g R 1 MM )1 M R M 0 V T N T f/A Jw 4 M M & R 4. m 9w MN m om u.

United States Patent 3,416,447 SADDLE FOR USE WITH FLEXIBLE WRAP- AROUNDPRINTING PLATES Norman J. Pozniak, Dearborn Heights, Mich., assignor toBrooks & Perkins, Inc., Detroit, Mich., a corporation of Delaware FiledOct. 10, 1966, Ser. No. 585,411 6 Claims. (Cl. 101415.1)

ABSTRACT OF THE DISCLOSURE A cylindrically shaped saddle formed of alight soft metal such as magnesium for mounting a flexible printingplate. Means connect one edge of the printing plate to one straight edgeof the saddle. A steel bar is movable circumferentially toward and awayfrom the other straight edge of the saddle. Guide means in the form ofelongated pins longitudinally slidable in sockets, connect the bar formovement circumferentially of the saddle toward and away from the edgethereof. The pins include axially elongated recesses and abutmentsextend from the sides of the sockets into the recesses. Both compressionsprings and adjustable abutments screws are provided between the edge ofthe saddle and the steel bar.

It is an object of the present invention to provide a saddle to which aflexible wrap-around type printing plate may be quickly and easilyattached and tensioned into proper operating conditions.

More specifically, it is an object of the present invention to provide asubstantially semi-cylindrical saddle having at one edge thereof a barhaving means thereon for clamping one edge of the printing plate, thebar being guided for movement toward and away from the edge of theprinting plate, and resilient means urging the bar away from theprinting plate to apply preliminary positioning tension thereto.

It is a further object of the present invention to provide a saddle asdescribed in the preceding paragraph including means for limiting themovement of the bar away from the edge of the printing plate.

It is a further object of the present invention to provide a saddle asdescribed in the foregoing in which the bar has a rounded corner aroundwhich one edge of the printing plate is bent.

It is a further object of the present invention to provide a saddle asdescribed in the foregoing in which the surface of the movable bar towhich an edge of the printing plate is clamped extends substantiallyradially of the saddle, thus requiring the edge portion of the printingplate to be bent through an angle of approximately 90 degrees.

Other objects and features of the invention will become apparent as thedescription proceeds, especially when taken in conjunction with theaccompanying drawing, illustrating a preferred embodiment of theinvention, wherein:

FIGURE 1 is an end elevation of the saddle showing a printing plateattached thereto.

FIGURE 2 is a side view of the structure shown in FIGURE 1.

FIGURE 3 is an enlarged fragmentary side view of an edge of the saddle.

FIGURE 4 is an end view of the structure shown in FIGURE 3.

In accordance with the present invention a substantiallysemi-cylindrical saddle is formed as shown in FIG- URES 1 and 2, havingan end configuration including a beveled surface 12 for use in mountingthe saddle on a press roll. Conveniently, these saddles are formed from"ice a light metal and excellent results are obtained when they areessentially formed of magnesium. In use each of the saddles has securedthereto in circumferentially tensioned condition a printing plate 14.

At one edge of the saddle 10 the printing plate 14 has a bent over endportion 16 engaging a substantially flat radial end surface 18 of thesaddle and it is clamped to the surface 18 by an elongated clampingstrip 20 secured to the straight edge of the saddle 10 by clampingscrews indicated at 22.

Means are provided at the opposite edge of the saddle for effecting apreliminary tensioning of the printing plate and for thereafteradjusting and equalizing the tension to effect proper securing andlocation of the plate on the saddle. This construction is best seen inFIGURES 3 and 4 to which attention is now directed. As best seen inthese figures a steel strip 24 is secured to the flat generally radialedge surface 26 of the saddle 10, this strip being secured by aplurality of screws one of which is illustrated at 28. The strip 24 isprimarily for the purpose of protecting the edge of the saddle becauseof the relatively soft material of which it is composed.

Associated with the saddle 10 is a movable clamping and tensioning bar30. The bar 30 is movable toward and away from the adjacent side surface32 of the strip 24 and it is guided for this movement by a plurality ofpins 34 slidable in cylindrical recesses or sockets 36 provided both inthe strip 24 and the adjacent edge portion of the saddle 10.Conveniently, the pins 34 may extend through openings 38 in the bar 30and be welded or otherwise rigidly and permanently secured to the bar bysuitable means such for example as the welded connection illustrated at40.

In order to prevent separation between the bar 30 and the saddle 10, thepins 34 are provided with axially elongated recesses 42 into which thenose of a retaining screw 44 extends. In FIGURE 3 a locking screw 46 isindicated outwardly of the retaining screw 44.

A plurality of compression springs 48 are provided in pockets 50 formedin the strip 24 and the adjacent edge portion of the saddle 10, theouter ends of the springs engaging the inner surface of the clamping andtensioning bar 30 to urge the bar outwardly.

As best seen in FIGURE 4, the clamping bar is provided with a fiatsurface 52 which extends generally radially of the saddle 10 and whichis interconnected to the outer cylindrical surface 54 of the saddle 10by the arcuately curved corner portion indicated at 56. Associated withthe bar 30 is a clamping strip 58 which engages the bent over portion 16of the printing plate 14 and is retained in clamping relation by aplurality of clamping screws indicated at 62.

, In addition, the bar 30 is provided with a plurality of threadedopenings 64 receiving adjustable abutment screws 66 for a purpose whichwill presently be described.

In use one edge of the flexible printing plate is suitably clamped toone edge of the saddle by the clamping bar 20, after which the printingplate is bent around the saddle and its opposite edge is bent around thearcuate corner 56 and across the outer flat surface 52 of the bar 30. Atthis time the abutment screws 66 are retracted and the bar 30 will beheld against the adjacent surface 32 of the strip 24. This edge of theprinting plate is either notched or apertured to receive the clampingscrews 62 and also to afford access to the abutment screws 66. Theclamping screws 62 are tightened to clamp the edge portion of theprinting plate against the bar 30 at which time the springs 48 areeffective to urge the bar 30 circumferentially away from the edge 32 ofthe saddle 10 and strip 24 to apply preliminary tension to the printingplate. Thereafter, the abutment screws 66 are adjusted as required toapply the requisite tension to the printing plate and to equalize thetension and effect proper positioning of the plate.

In practice, the printing plate may be stripped to a key line for properlocation, sheared, the ends crimped to engage the edge surfaces of thesaddle, and these crimped edge portions punched to provide openings orslots for the reception of clamping screws and access to the abutmentscrews as previously described.

The location of the printing plate on the saddle may thus be accuratelycontrolled in accordance with suitable indicia provided on the surfaceof the saddle, thereby insuring the require registration betweenimpressions in multicolor printing operations.

The drawing and the foregoing specification constitute a. description ofthe improved saddle in such full, clear, concise and exact terms as toenable any person skilled in the art to practice the invention, thescope of which is indicated by the appended claims.

What I claim as my invention is:

1. A saddle for mounting a flexible printing plate to a press roll, saidsaddle being semi-cylindrically shaped and having two straight paralleledges at opposite sides thereof, means at one straight edge of saidsaddle for securing one edge portion of a flexible printing platethereto, a bar at the opposite straight edge of said saddle, guide meanscomprising elongated pins slidable longitudinally in sockets connectingsaid bar to the said opposite edge of said saddle for movement of saidbar circumferentially of said saddle toward and away from said oppositeedge, means for clamping the opposite edge portion of said flexibleprinting plate to said bar, resilient means interposed between said barand the said opposite edge of said saddle urging said bar away from saidsaddle, stop means acting between said bar and said saddle to limitseparation therebetween, and adjustable abutment screws extendingthrough said bar and engageable with the said opposite edge of saidsaddle.

2. A saddle as defined in claim 1 in which said stop means comprisesaxially elongated recesses in the pins of said guide means, andabutments extending from the sides of said sockets into said recesses.

3. A saddle as defined in claim 1 in which said pins are fixedlyconnected to said bar, and said sockets are formed in the adjacent edgeof said saddle.

4. A saddle as defined in claim 1 in which said saddle is formedessentially of magnesium or a magnesium alloy, and comprises a steelstrip permanently affixed thereto to form the said other straight edgeof said saddle.

5. A saddle as defined in claim 4 in which the sockets are elongatedguide sockets formed in the other straight edge portion of said saddle,the sockets extending through the steel strip into the magnesium ormagnesium alloy, and the pins are elongated guide pins fixedly connectedto said bar and slidable longitudinally in said sockets.

6. A saddle as defined in claim 5 in which the stop means comprisesaxially elongated recesses provided in the sides of said guide pins, andabutments extending from the sides of said sockets into said recesses.

References Cited UNITED STATES PATENTS 2,265,005 12/1941 Read 101415.12,970,540 2/1961 Wirth 101415.1 3,062,141 11/1962 Graves 101415.13,107,609 10/1963 Haramisa 101-378 3,218,970 11/ 1965 Helmlicher et al.7

FOREIGN PATENTS 770,356 6/1934 France.

ROBERT E. PULFREY, Primary Examiner.

F A. WINANS, Assistant Examiner.

